Malicious PDF — malware analysis report

Static analysis result for SHA-256 f38d9075e99173ab…

MALICIOUS

PDF

93.4 KB Created: 2021-08-16 07:50:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 91a1f5268468a80ed7f1cfef2439f6a7 SHA-1: 7f4120e056c875b355e2670306c294f8077d7742 SHA-256: f38d9075e99173ab7b763d033a1ec3bbeadc88e14eb6fbe590bf1e93c5162e8d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. The ML classifier and ClamAV also strongly indicated maliciousness, specifically phishing and trojan behavior. While no scripts were directly extracted, the nature of the link farm suggests an attempt to redirect users to malicious sites, likely as part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://hieuchuan.com/upload/files/legatiwobofu.pdf
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16102b9daabff5---giwuso.pdf
    • http://mashtalkandil.com/userfiles/file/jefomibu.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f9f77cedd---mujul.pdf
    • https://ekselantechnology.solutions/ckfinder/userfiles/files/13667635020.pdf
    • https://meganimal.pt/site/upload/file/35157654341.pdf
    • https://otelnamore.com/wp-content/plugins/super-forms/uploads/php/files/d43cfa533ba6af46d026f6a533dbbd95/digupozak.pdf
    • https://thietbivesinhanhhuy.com/asset/files/80543180192.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/6d608469054474fb877025178baf8333/25349165196.pdf
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/14a6cf54b70fa6145506a4a027b6bd88/59552750181.pdf
    • https://promise-land.com/upload/file/30176549308.pdf
    • http://rainesclassof1980.com/clients/3/31/314d3ac3c31ee16cfc8f78d457af0ebc/File/telajozakizojopeso.pdf
    • http://sendedianqi.com/upload_fck/file/2021-6-28/20210628125430854075.pdf
    • http://vdavloeren.be/userfiles/files/zusijogenobusepedupoxina.pdf
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1608093eddb1f1---pakonaxipotekazegi.pdf
    • http://elisa5888.com/shopadmin/upload/files/fazumemilaj.pdf
    • https://craftsmancuttingdies.com/wp-content/plugins/super-forms/uploads/php/files/fmorh3f10f9g0chtb5ahtsreaf/powafowufubadusofuvanak.pdf
    • http://canoeing.by/pics/files/36833894228.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8f8050ae7---xaxagotiwikefo.pdf
    • https://tecnicadovolante.com/images/file/semujupito.pdf
    • http://brenno-tojestto.pl/userfiles/file/39245550787.pdf
    • https://skillmapmagazine.com/ckfinder/userfiles/files/88409913695.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+get+all+answers+on+schoology+quiz
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef40.bin
3b3875d2650628d0de0269c987b40e07b8cdecb9dc413d04a6735f04e3302c5b
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF40 16872 bytes
font_01_sfnt_off000106a3.bin
a4cec68d5f7ef7cd9a383f0727db7a94cc9aa6a6f1baeb753a5e9b8be1103baa
pdf-font-stream PDF embedded font (sfnt) at offset 0x106A3 17208 bytes
font_02_sfnt_off000133c0.bin
0dde32b38c1f390aa80139ff8779e6791fc22de78451d8e45a7a177eca7e91b9
pdf-font-stream PDF embedded font (sfnt) at offset 0x133C0 11008 bytes
font_03_sfnt_off00014d18.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14D18 16792 bytes